1976 40hp Evinrude Armature Plate Movement & Points Contact. Abnormal?

[mikear]

Let me start off by saying the motor is running very well minus the slight WOT surge. This was not the case prior to last week. Last week I removed the flywheel and found one of the two sets of points had corroded. I cleaned them up using 220 grit sand paper. I removed the armature plate and inspected its bearing (Delrin ring), etc. All looked well and I lubed them up with LU oil as stated in the manual. I put everything back together.

I received the ignition tune up kit on Friday (condensers, points). Today, I installed the kit without removing the armature plate. I noticed some play in the armature plate. This play was slightly up and down thus allowing a slight tilting movement also. Side to side play is virtually non-existent. I put the flywheel back on and when turning the flywheel the armature plate moves up and then back down when rotating. It's not hitting anything during rotation. I believe it's the magnets on the flywheel picking up the armature plate when it passes the coils. Is this something to be concerned about? I am hesitant to run this thing without being sure.

Also, the new points I received make ~10-20% contact on their contact surfaces. The old points that I removed had 90-100% contact. Are you supposed to sea/bed new points together or will they break in during operation?

Thanks in advance!

 

[mikear]

Re: 1976 40hp Evinrude Armature Plate Movement & Points Contact. Abnormal?

Started the motor in a drum of water and let it idle. The armature plate does not move like before when the motor is running. I placed my hand on the armature plate to make sure the RPMs were not visually masking the movement. It stays put. I guess I'll give it a try at the lake when I get a chance.

Anyone have a older 40hp with the magneto ignition similar to my engine that they could check? If you grab the wiring going into the armature and move it up and down (with the flywheel installed) the plate moves.

I'm still not sure about the points but it idles fine in the barrel.

Thanks.

 

[kbait]

Re: 1976 40hp Evinrude Armature Plate Movement & Points Contact. Abnormal?

If the plate's not moving laterally (side to side) the point gap shouldn't change. The up/down movement shouldn't change the gap, and you say it doesn't bounce around when testing, so I wouldn't worry too much about it. I find that aftermarket pointsets don't usually match up well, and I've bent them to 'face-up' correctly. I usually clean up the original points w/a file.. then a fine file to get 'em shiny and reset to .020". Don't use sandpaper, as the grit can get caught in the mating surfaces and fail quickly. If your motor is idling well now, I wouldn't go in just to re-face the points, as they're obviously working now.. Good luck!

 

[mikear]

Re: 1976 40hp Evinrude Armature Plate Movement & Points Contact. Abnormal?

If the plate's not moving laterally (side to side) the point gap shouldn't change. The up/down movement shouldn't change the gap, and you say it doesn't bounce around when testing, so I wouldn't worry too much about it. I find that aftermarket pointsets don't usually match up well, and I've bent them to 'face-up' correctly. I usually clean up the original points w/a file.. then a fine file to get 'em shiny and reset to .020". Don't use sandpaper, as the grit can get caught in the mating surfaces and fail quickly. If your motor is idling well now, I wouldn't go in just to re-face the points, as they're obviously working now.. Good luck!

Thanks for the advice. The replacement set is original OMC parts (ignition tune up kit). The package looked old but they were still sealed. I will put it on the water and see what it does. The points appeared that they could be bent to match up the mating surfaces, that's why I asked if this was correct.